Our objective is to develop a reasonably priced commercial tissue culture medium which can be used for the cultivation of microvessel endothelial cells. This medium, which will be named MICRO GRO, will have market application in research areas pertaining to tumor angiogenesis, microangiopathy, inflammatory events and potentially vascular surgery. The development of this medium will allow for the expansion of cell populations isolated from various tissues. We have found the combination of a mucopolysaccharide and ENDO GRO(TM), a retinal-derived growth factor produced by VEC TEC, Inc., acts synergistically to promote the growth of microvessel endothelial cells from murine hearts. MICRO GRO promotes enhanced growth and shortened replication times when compared to the state-of-the-art media. This study will focus on expanding these initial studies by evaluating the ability of MICRO-GRO to support the growth of murine microvessel endothelial cells from additional anatomic sites and determine if MICRO GRO can extend the in vitro life-span of these cells in tissue culture.